An ink jet printing system includes components such as a drop generator with an orifice structure for making an array of ink jets that project ink drops, a charge device to selectively charge the ink drops formed by the drop generator, and a catcher to collect selectively charged drops not intended for printing. An eyelid is a device used to seal against the catcher to facilitate the startup sequence of the ink jet printing system. The eyelid is conventionally operated to seal against the vertical surface, and the catcher flow pan of the catcher to prevent leakage of ink out of the printhead before a catch state is established for the ink jet printing system.
Typically, after the catch state has been established for the ink jet printing system, the eyelid is held closed until the printer is required to print, at which time the eyelid is opened and allows the print drops to exit through a narrow slit between the eyelid seal and the catching surface.
Migration of the ink can reach the charging leads on the charge device, and can create a short between the leads. Typically, the ink jet printer responds by shutting down the printhead and fluid system, and alerting the operator to the problem. The operator has to stop his print job and service the printer, usually by restarting it. Also, the migrating ink can dry and interfere with the impacting drops, causing them to skip off the catcher and hit the print media, thus creating a printing defect. The operator must then service the printhead, usually by manually shutting down the printhead and fluid system, followed by a restart or cleaning sequence and restart. Again, the print job has to be stopped.
In the cases of the operator's intervention and stopping of the print job, the productivity of the printing process is impaired and the reliability of the printer is impacted.
A need exists to improve the reliability of the ink jet printer by reducing the shorting out of the leads and reduce the effect of the migrating ink on the catcher.
The present embodiments described herein were designed to meet these needs.